Manufacture of artificial filaments



Patented Aug. 7, 1934 UNITED STATES 1,969,689 PATENT OFFICE MANUFACTURE OF ARTIFICIAL FILAMENTS Thomas H. Byron, Elizabethton, Tenn., assignor to North American Rayon Corporation, New York, N. Y., a corporation of Delaware No Drawing. Application April 26, 1932, Serial No. 607,675

4 Claims. (01. 10640) More especially, the invention concerns a novel method for producing filaments, films, threads and the like having a matt appearance, or dull lustre.

. One object of the present invention is to provide a process which will produce filaments, etc., of the class described, in a certain, economical manner.

Another object is to provide a method for producing dull lustre yarn.

Other objects will become apparent from a study of the following specification and claims.

In the manufacture of artificial filaments, the filaments are spun or extruded through fine orifices into a coagulating medium. When hardened, they are after-treated and prepared for the trade.

In order to make this clearer, the following discussion will refer specifically to the viscose process, but it should be understood that the present invention is not limited thereto. A similar discussion might also be written with reference to the other processes.

In the viscose process, a viscose solution is made up and extruded through fine openings in a spinning nozzle or spinneret, into a coagulating medium. This medium is practically always a bath of liquid, through which the filaments are guided. They are usually collected on spools and then wet-treated or after-treated. This treatment includes washing, desulphurization, deacidification, bleaching, drying, etc. The finished filaments, either twisted or untwisted, are then supplied to the weaver, knitter, etc.

The ordinary filaments thus formed tend to possess a high lustre, which, in some cases, is not.

as desirable as a low lustre. Various methods and means for producing a low lustre have been devised, but those pertaining solely to the viscose process may be divided into four general classes.

1. In the first class, a special type of precipitating bath may be employed.

2. In the second method, a dulling plastic layer may be superimposed upon a high lustre soluble in water, are added to the solution of viscose prior to its spinning, or are ground up and mixed with the alkali cellulose prior to the production of the viscose.

As an example of the present process, the oxalates of titanium are definitely mentioned, but it should be understood that any water insoluble organic salts of titanium producing the desired results may be used.

The following oxalate and compound oxalates of titanium may be employed:

T1203 (C204) -12Hz0 Ti (NH4) (C204) H2O BaTiO (C204) 2 21-120 K'Ii (C204) 2 H2O Each of these organic salts is water insoluble. Only a very small percentage of the salts need be employed.

Example.To a viscose solution or to the alkali cellulose to be used to make the same, are added from 2% to 4% of potassium titanium oxalate, KTi(C2O4)2 H2O, in the form of a fine dispersion. If this compound is added to the alkali cellulose, it is added in an amount which will correspond to 2% to 4% of the ensuing viscose solution to be formed from the alkali cellulose.

I have found that as little as of this salt will give good results, and therefore do not wish to limit myself to the amount specified.

In producing dull lustre yarns from cuprammonium solutions, the compounds may be added at any desired stage of the production, but it is preferred that the compound be added, and finely dispersed through, the finished cuprammonium solution.

The dispersion may be accomplished by taking a small amount of the viscose or cuprammonium solution, for example, and finely dispersing the ground compound therein. This small portion is then added to, and thoroughly mixed with, the remainder of the solution.

Having now set forth my invention as required by the patent statutes, what I desire to claim is:

1. In the manufacture of dull lustre artificial filaments, and the like, the step of incorporating in the solution to be spun an insoluble oxalate of titanium.

2. A spinning solution for artificial silk having incorporated therein a small percentage of insoluble titanium oxalate.

3. A viscose spinning solution containing dispersed therein not more than 4% of titanium oxalate bearing the formula T1203 (C204) 12.H20.

4. A cuprammonium spinning solution containing dispersed therein not more than 4% of titanium oxalate bearing the formula T1203 (C204) 12.H20.

THOMAS H. BYRON. 

